1. Field of the Invention
The present invention relates to a steering apparatus and a steering controller.
2. Description of Related Art
As a steering apparatus and a steering controller mounted in a vehicle, for example, a lane-following running controller is disclosed in Japanese Patent Application Publication No. 2003-063437 (JP 2003-063437 A). The lane-following running controller estimates a state quantity including at least a disturbance torque applied to a steering apparatus on the basis of a running lane and a running state of the vehicle, feeds the estimated state quantity back to calculate a command torque, and generates a steering torque corresponding to the command torque. At this time, the lane-following running controller separately estimates the disturbance torque as a high-frequency component and a low-frequency component and sets the feedback quantity of the high-frequency component of the estimated disturbance torque to be smaller than the feedback quantity of the low-frequency component.
In the lane-following running controller described in JP 2003-063437 A, a driver's steering input can be easily reflected, for example, by setting the feedback quantity of the high-frequency component to be relatively small. However, inversely, a variation in torque due to disturbance of the high-frequency component increases and tends to be unstable and thus there is room for improvement in terms of improvement of a steering sensation.